SITE INFORMATION AND CORRESPONDENCE_FILE 2

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V %W� Project No, 034-00009 Page No. 2 September 9, 1989. Upon completion of the tank removal, two soil samples and one groundwater sample were collected directly below the tank at 15 feet below surface grade (bsg). Based on laboratory analytical results from the excavation samples, H&H determined that hydrocarbon contamination was present in soil at maximum concentrations of 330 milligrams per kilogram (mg/kg) gasoline, 16,000 micrograms per kilogram (µg/kg)total xylenes, and 3,000 pg/kg ethylbenzene. In addition, hydrocarbon contamination was present in groundwater at concentrations of 4.7 milligrams per liter (mg/L) gasoline, 33 micrograms per liter (µg/L) benzene, 200 }tg/L total xylenes, and 110 p.g/L ethylbenzene. Concentrations of kerosene, diesel, benzene, and toluene were not detected in the soil samples at or above the respective laboratory reporting limits. Concentrations of kerosene, diesel, and toluene were not detected in the groundwater sample at or above the respective laboratory reporting limits. In a workplan dated May 13, 1991 (Attachment 4), the installation of eight groundwater monitoring wells was proposed for a 62-arce parcel of property that included the subject. The placement of the wells was designed to investigate the area of the subject site's former UST along with potential hydrocarbon contamination not related to the subject site (The larger off-site investigation ultimately received closure from the SJCDEH). The workplan indicates that the SJCEHD was involved in approving the placement of these wells. According to the SJCEHD, a permit for the installation of these wells was approved and a permit was issued on May 21, 1991 (Permit#91-1193). According to a Report of Findings, dated July 22, 1991 (Attachment 5), Toxic Technology Inc. (TTI), installed one monitoring well (MW-1) in accordance with the May 13, 1991, workplan. The well was installed in May 1991 to a depth of 22 feet bsg in the immediate vicinity of the former UST. Soil samples were collected for laboratory analysis of petroleum hydrocarbons from the boring (B-1) for the well at approximately five-foot intervals (i.e., at 9, 14, and 18 feet bsg). A groundwater sample was collected from the well after its development and purging of approximately four volumes of groundwater. The samples were analyzed for petroleum hydrocarbons using EPA Methods 8015m and 8020. Concentrations of petroleum hydrocarbons that were tested for were not detected at or above the respective laboratory reporting limits in either the soil or groundwater samples. The sample collection protocol and well construction/development is detailed within the attached July 22, 1991, report. A detailed "soil layer description" and boring log for B-1/MW-1 and a table of groundwater analytical results is also included in the attached report. While several pages of laboratory-supplied analytical results and a chain-of-custody (COC) record are included in the July 22, 1991, report it appears that the copy of the report that provided to Krazan does not contain all the material that pertains to well MW-1. This may be due to pages becoming separated during many years of storage. KRAZAN&ASSOCIATES,INC. Offices Serving the Western United States 3400009.1tr